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 Tuesday night Christy Crites and Shannon Brady of CMT presented
the results and their recommendations for the LTCP to the council.
The Environmental Protection Agency has established rules for
wastewater release into public waterways that are designed to
prohibit the amount of raw sewerage that is allowed to go into a
waterway. In the perfect scenario, the EPA would like to see every
city have a system that separates storm water runoff from sewerage.
However, in many cases, city’s operate with what is called a
Combined Sewer, which at some point in time raw sewerage and storm
water pass through the same underground pipes. Because converting to
separated sewers would be a huge undertaking financially (about $100
million for the city of Lincoln), the EPA established alternatives
they consider to be more affordable but with similar outcomes.
Tuesday evening, Crites offered up a simple explanation of what a
combined sewer is. Using a powerpoint slide, she explained that the
underground system that runs through the city transports both storm
water and sewerage. The main pipe will eventually lead to a public
waterway with secondary pipes fingering off the main and going
directly to the sewer treatment plant. In the main pipe, there are
diversion dams that are constructed to help divert sewerage into the
proper secondary pipes. In occasions where there is heavy rainfall,
the storm water and sewerage combined may reach such a volume inside
the main pipe that the liquid flows over the diversion dam. This
overflow is called a CSO. By EPA standards, combined sewers are
allowed four CSO’s per 12 month period. However, Crites said CMT’s
study indicated that the city of Lincoln has the potential for 49
such overflows per year.
In the city of Lincoln there are two locations where this overflow
can occur; at Union Street flowing into Brainard’s Branch and at the
Waste Treatment plant flowing into Salt Creek.
Crites explained CMT had looked at alternatives to address this
including complete separation of sewerage from storm water and
multiple alternatives that involved maintaining the combined sewer
but separating the water at the collection points.
The recommendation they were going to make to the city would address
the overflows without re-designing the entire sewer system, and
these were also the alternatives she thought were most financially
attainable for the city.
At the waste treatment plant, Brady explained the CMT
recommendations. The plan would be to modify an existing clarifier
pond to take in the overflow. On Union Street, the plan would
include moving the pump station across the road from where it is now
to a green space. Then upgrade the station with high and low volume
pumps, backflow prevention, and possibly a holding tank for extreme
excesses. Crites said the modifications at the waste treatment
plant would include a new pump station and new screening facilities.
The plan would modify one existing clarifying pond to take in the
overflow and temporarily store it. After the event, the product in
that now holding pool would be transferred over time through the
primary treatment process and eventually it would go gradually into
the full treatment process before being released into Salt Creek.
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The speakers explained that this was an alternative that would
address the EPA requirements satisfactorily, but not without some
significant investment. For the modifications at Union Street, they
estimated the cost to be $1.9 million. At the waste treatment
facility, they said the cost would be approximately $13.5 million.
The EPA does offer financial assistance on these projects for
qualifying cities. Crites and Brady explained that in looking at the
current sewer fee structure for the city of Lincoln, the rates have
been held low. Because of this, the EPA says that the city can raise
its rates and manage to pay the approximately $15 million on its
own, without financial assistance. This was not what the Council was
hoping to hear. The council needs to approve this plan, and it
must be submitted to the EPA by May 1st. Once it is approved, Crites
said the clock starts ticking, and the city will have five years to
implement the plan.
During the discussion period, the first concern voiced, "Is the EPA
going to continue changing their rules?" Not all that long ago the
city invested $9 million in the waste treatment plant, and within
just a couple of years found out that the plant was no longer in
compliance with EPA standards. Some wondered if this would happen
again this time.
Crites said that is not predictable, but she doesn’t see anything on
the horizon. She said typically when rules start changing, the
changes do not first take effect in the Midwest. There are currently
no water quality standard changes going on in the coastal regions,
so that is a good sign.
Waste treatment manager for the city of Lincoln, Tim Ferguson, also
noted that if changes are made by the EPA before the city project is
fully implemented, amendments can be made to the overall plan to
accommodate those changes.
Another question coming from the aldermen was, "How long would it
take for the EPA to approve the plan?" Crites estimated a year
though she said some had been approved in as little as six months.
A motion to approve the plan as presented by Crawford, Murphy and
Tilly will be on the Monday night voting agenda. Looming in the
future for the city will be determining how to pay for the project.
[Nila Smith]
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